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Pinpoint Test P: The Malfunction Indicator Lamp (MIL) Is Never/Always On




Instrumentation, Message Center and Warning Chimes

Pinpoint Test P: The Malfunction Indicator Lamp (MIL) Is Never/Always On

Normal Operation

The Malfunction Indicator Lamp (MIL) informs the driver of a malfunction in the powertrain that affects the vehicle emissions system. The Instrument Cluster (IC) illuminates the MIL when a fault condition is detected by the PCM and a DTC has been set. The IC flashes the MIL when a misfire has been detected by the PCM. The IC receives the MIL data from the PCM over the High Speed Controller Area Network (HS-CAN).

This pinpoint test is intended to diagnose the following:

- PCM
- IC


PINPOINT TEST P: THE MIL IS NEVER/ALWAYS ON

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P1 RETRIEVE THE RECORDED DTCs FROM THE PCM KOEO SELF-TEST


- Retrieve the recorded PCM DTCs from the Key ON Engine OFF (KOEO) self-test.
- Are any PCM DTCs recorded?

Yes
REFER to Computers and Control Systems.

No
GO to P2.

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P2 CARRY OUT THE IC INDICATOR LAMP ACTIVE COMMAND USING THE SCAN TOOL


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC DataLogger.
- Select the IC MIL active command (MIL_IC) on and off. Observe the MIL.
- Does the MIL illuminate when selected on and turn off when selected off?

Yes
INSTALL a new PCM. REFER to Electronic Engine Controls Service and Repair. TEST the system for normal operation.

No
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.

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